The present invention relates generally to medical devices for applying pressure to a puncture site to aid hemostasis of the puncture site, i.e., blood clotting, for sealing the puncture site, and particularly to a hemostasis pressure pad carried upon an adjustable band or strap for convenient and single use.
Certain medical procedures require insertion of a needle into an artery or a vein of the patient, either momentarily or under prolonged circumstances, to inject or withdraw fluids into and from the blood circulatory system. Withdrawal of the needle from the artery or vein requires immediate application digital pressure to the puncture site to prevent blood flow, and requires continued application of pressure for sufficient time to allow natural blood clotting to seal the puncture site. The applied digital pressure must be present for a significant time, e.g., on the order of 15 minutes, for the blood to clot and seal the puncture wound by way of the body's own nature healing process.
For example, persons suffering kidney impairment cannot maintain a clean blood supply and must have their blood supply cleansed by a dialysis or artificial kidney machine. In such procedures, the kidney machine is temporarily integrated into the blood circulatory system to remove blood from a vein, i.e., blood carrying impurities from body organs and tissues; filter that blood within the artificial kidney machine; and return the cleansed blood to the circulation system at an artery for delivery to the body organs and tissues in the normal course. Thus, to perform dialysis the patient's blood system is accessed at two locations, i.e., to take and return blood. Such access is accomplished by inserting needles through the skin and into the blood circulatory system.
For most dialysis patients, however, the repeated access to the blood system by needles would damage the veins and arteries. To avoid such damage, grafts are placed under the skin surface and in series with the blood system to allow frequent access by needle to the blood system without repeatedly puncturing the patient's veins and arteries.
When the dialysis treatment is complete, the needles are removed, but the associated bleeding must be controlled until the patient's natural healing process, i.e., blood clotting, seals the access site to the blood system. Thus, as each needle is withdrawn from the body, either the medical attendant or the patient must maintain digital pressure against the puncture site until hemostasis, i.e., sufficient natural blood clotting to seal the puncture, is achieved. Typically such digitally applied pressure has required up to 15 minutes before achieving hemostasis.
The process of aiding hemostasis by application of pressure has been performed by trained medical personnel with their fingers applying the needed pressure. Devices have been developed to simulate the required manual digital pressure in aid of hemostasis to more quickly free the medical attendant for other duties.
For example, U.S. Pat. No. 4,829,994 issued May 16, 1989 to Kurth shows a pelvic apron including a groin strap for securing what is described as a shaped mass or "pellet" in position over an incision in the femoral artery following catheterization of the patient. The pellet provides direct pressure upon the incision site by virtue of the contour of the pelvic apron piece and groin strap which, when wrapped about the body, secures and presses the "pellet" over the incision point to thereby halt the flow of blood until the artery repairs itself by natural clotting of the blood.
The objective of the Kurth device is to provide a sector of a sphere with a flatten pole to serve as a replacement for the equivalent amount of folded gauze to define the pressure point against the femoral arterial or venous incision, but this objective reveals the inadequacy of such a pellet formation for the intended purpose. In particular, the skin contacting surface of the pellet contacts the incision point at the artery as well as a significant area of skin immediately adjacent the artery. The large surface area of the pellet in contact with the skin distributes the downward force created by the pelvic apron and groin strap over an equal amount of skin surface. Since the diameter of the pellet is stated to be approximately 2 and 7/8 inches, the skin area onto which the downward force is distributed can be taken as being approximately a circle having a diameter of 2 and 7/8 inches with the incision site at the artery being at the center of the circle. This distribution of force over the surrounding area of the incision site requires that a significant amount of pressure be applied to the pellet by the pelvic apron and groin strap such that the pellet may stop the bleeding from the artery. Even with such strong pressure applied to the pellet, the artery can require a significant period of time to heal due.
U.S. Pat. No. 4,182,338 issued Jan. 8, 1980 to Stanulus shows a pressure appliance having a truncated, pyramid-shaped body and a cylindrical pressure applicator. Although the pressure appliance of the Stanulus device attempts to provide a localized pressure point for the applicator as disposed upon a generally flat surface of the appliance, it fails to effectively direct pressure to the artery itself. Instead, the downward force of the applicator and the surrounding surface as applied by securing straps is distributed in the area of the skin surrounding the artery or vein. The skin-contacting surfaces of the applicator and its surrounding surface lie in spaced, parallel planes whereby any pressure directed toward the skin of the body is distributed over an area of skin equaling the dimensions of the rectangular surface surrounding the applicator. The blunt end of the applicator further indents the skin an equal distance along all points defined by the surface of the applicator at its blunt end. The artery in this situation is then receiving the same amount of pressure as in the surrounding area of skin contacted by the blunt end of the applicator and, to a slightly lesser extent, the surrounding area of skin contacted by the surface about the applicator is receiving the same amount of pressure.
U.S. Pat. No. 5,010,902 issued Apr. 30, 1991 to Rambo discloses a compression orb for use in combination with appropriate bandages to apply a direct force to an arterial or venous puncture site. The device directs and focuses pressure upon the arterial or venous puncture site such that bleeding therefrom is blocked while normal systemic arterial pressure is maintained. Also, at the same time the device allows visual inspection of the puncture site.
U.S. Pat. No. 4,572,182 issued Feb. 25, 1986 to Royse and entitled Notched Pressure Pad For An Artery Clamp shows a clamp stand with an arm extending therefrom and carrying at its distal end a notched pressure pad as an artery clamp. The skin contacting surface of the pad is presented as a generally flat disk shaped member having a V-shaped notch cut therein. Other than the V-shaped notch, the undersurface, i.e., skin contacting surface, of the pad is generally flat. The notch accommodates the inclined orientation of the needle for placement of the pad prior to needle removal.
U.S. Pat. No. 4,742,825 issued May 10, 1988 to Freund et al and entitled Adjustable Compress Apparatus also shows a clamp arrangement including an arm carrying at its distal end a compress pad. The undersurface of the pad, i.e., the skin contacting portion, is generally planar, but includes a relief area in the undersurface which is spaced at its closed inner end from the center of the pad and is extended therefrom to an open outer end at a peripheral edge portion of the pad. The presence of the relief area allows catheter removal with the pad in place and provides a means of locating the pad properly with respect to the puncture site. Due to the shallowness of the groove, the pad applies pressure to the patient's skin in the region of the groove.
U.S. Pat. No. 3,779,249 issued Dec. 18, 1973 to Semler and entitled Artery Clamp shows an artery clamp having an arm carrying at its distal end a pad. The undersurface of the pad, i.e., the skin contacting surface, appears to be a planar surface bearing upon the puncture site to be compressed. More particularly, the pressure pad is described as a "generally disk shaped base on top of which is formed an integral mounting boss."
Other instruments used in connection with accessing a patient's blood circulatory system relate to the stabilization of the blood vessel during access, but do not contemplate use in aid of hemostasis.
U.S. Pat. No. 2,712,314 issued Jul. 5, 1955 to G. C. Kohl and entitled Anesthesia Needle Guide shows a handheld device for permitting injections of anesthetics locally into the wall of a cavity within the human body. The device appears to be directed towards the positioning of a guide relative to a desired puncture site and the use of the guide to bring the needle to the selected puncture site.
U.S. Pat. No. 4,314,568 issued Feb. 9, 1982 to Loving and entitled Vascular Stabilizer shows a disposable device for stabilizing a vessel during access thereto by a needle. The device includes two half body portions, each half body portion having a vascular stabilizing rib thereon such that the stabilizing ribs may be brought along the sides of a blood vessel. The vessel is then held in place for access thereto by a needle. The device has no mechanism for applying pressure to the puncture site of the needle following needle removal.
U.S. Pat. No. 1,561,116 issued Nov. 10, 1925 to Silliman shows a vein stabilizer comprising generally a planar surface held against a patient's skin and including a notch in the planar structure. The vein may be positioned along the notch in order to stabilize the vein during access by a needle. The device has no structure for applying pressure to the puncture site of the needle.
While the above described hemostasis appliances have been successful in achieving hemostasis, the pressures applied and time required to achieve hemostasis as well as an ability to maintain the appliances sanitary have not been completely satisfactory. Also, most existing hemostasis appliances are difficult to attach to the patient, and typically require two hands for placement, alignment, and engagement of the pad against the puncture site. Accordingly, it is desirable that a hemostasis appliance more conveniently apply the required pressure to a puncture site and more efficiently, i.e, quickly, achieve hemostasis